Tic 36v4 Limit Switch Software Debounce


Is it possible to configure a software debounce for the limit switch inputs on the Tic 36v4 Stepper Controller (if not, I suppose this is a new feature request)?

I am trying to use the Homing feature on the Tic 36v4 Stepper Controller by configuring the TX and RX pins on the driver to be forward and reverse limit switches respectively.

However, my mechanical limit switches I’ve set up with the input pins on the 36v4 are quite noisy (especially due to the stepper’s vibration), causing homing to complete sporadically. A software debounce would be great here if possible! Thanks - love the product!


The Tic’s limit switch inputs cannot be configured to do debouncing; thank you for the suggestion. We have not heard of debouncing problems while using the homing feature. Could you tell us more about what exactly goes wrong during the homing process? Additionally, have you tried using any hardware debouncing to see if it helps?


My first suggestion is find a different limit switch if possible, are you using a snap action switch or a mushy push button switch. For hardware debouncing there are a number of methods, the simplest probably being an RC circuit. Look up switch debouncing circuits, there are lots. I’m not an EE, so something like a Max 6818 chip that is purpose built is perhaps the easiest way if not build thousands of systems. It is an expensive chip for what it seems to do ($2-$3), but otherwise easy to implement.

I also have limit switch/homing issues (T500). I’ve tried two types of switches: reed switches and these Omron switches: https://www.digikey.com/en/products/detail/omron-electronics-inc-emc-div/SS-5GL13/369879 . I get the same issue with both: sometimes homing does not back away from the active position so the limit switch state remains active. Both of the switches seem to have a little bounce but I’d imagine the delay after reaching active should take care of it. Is there any way to increase the 20 milliseconds delay? That would be so much easier than adding debounce to all the limit switches.

Hello, jr2.

Unfortunately, there is currently no way to change the 20ms delay. If you are controlling the Tic from a microcontroller or computer, you might consider programming it to wait a short time after the end of the homing procedure, check to see if the switch is active, and if it is, you can run the homing procedure again (which should cause it to move away from the switch).


Hi Brandon,

Thank you very much for the reply. That’s a great suggestion! Based on a couple of tests in the Tic Control Center it seems to work.

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